Objective:To study the molecular mechanism of Buyang Huanwutang in promoting the maturation of neovascularization by regulating the signal transduction of transforming growth factor-β1 (TGF-β1)/drosophila mothers against decapentaplegic protein (Smad4) gene under hypoxia condition. Method:The three-dimensional model of vascularization was established by implanting abdominal aorta in Matrigel matrix. There were four groups

namely the normal control group

the hypoxia model group

the Simvastatin treatment group and the Buyang Huanwutang treatment group. After incubation under normoxia condition for 5 days

the model group was given hypoxia intervention for 24 hours

while the treatment groups were respectively given Simvastatin (10 μg·L-1) and Buyang Huanwutang (10%)

and the control group was incubated under normoxia for six days. The growth of neovascularization was observed under inverted microscope. The content of TGF-β1 in culture medium of neovascularization was detected by enzyme linked immunosorbent assay (ELISA). The gene expressions of TGF-β1 and Smad4 in neovascularization were detected by Real-time PCR. The protein expression of neural-Cadherin (N-Cadherin) was detected by Western blot. Result:The results of each experimental group displayed neovascularization under inverted microscope. Compared with the normal group

the number of stable neovascularization was reduced in the model group. After the treatment with Buyang Huanwutang

the number of stable neovascularization was increased

compared with the model group. The results of ELISA showed that the content of TGF-β1 was significantly decreased (P<0.01) in the model group

compared with the normal group. After the treatment with Buyang Huanwutang

the content of TGF-β1 was increased (P<0.05)

compared with the model group. The results of Real-time PCR indicated that the mRNA expressions of TGF-β1 and Smad4 in the model group were lower (P<0.05) than those of the normal group. After the treatment with Buyang Huanwutang

the mRNA expressions of TGF-β1 and Smad4 were higher (P<0.05) than those of the model group. The results of Western blot demonstrated that the protein expression of N-Cadherin was lower (P<0.05) in the model group than that of the normal group. After the treatment with Buyang Huanwutang

the protein expression of N-Cadherin was higher (P<0.05) than that of the model group. Conclusion:Buyang Huanwutang could promote the neovascularization under hypoxia condition. Its mechanism is correlated with the activation of TGF-β1/Smad4 signal

which then starts the synthesis of downstream protein N-Cadherin and forms the close intercellular junction.